Regardless of what form symptoms take (SKIN RASH, tingling around the MOUTH, DIARRHEA), a type I hypersensitivity reaction is a systemic response-it affects and involves the body as a whole.
How to Read Your Eyeglass Prescription. The first step to understanding your eyeglass prescription is knowing what OD and OS mean. They are abbreviations for oculus dexter and oculus sinister, which are Latin terms for right eye and left eye.
It may look a bit daunting, but understanding your eyeglasses prescription is easier than you might have thought. The two most important of these mystery terms and abbreviations are OD (Oculus Dextrus) and OS (Oculus Sinister). These are Latin terms that mean right eye and left eye, respectively. Listed after these OD and OS abbreviations are numbers preceded by either a plus sign (+) or a minus sign (-).